Motor vehicle



July 19, 1932.

MOTOR VEHICLE Filed 001;. 3l. 1931 Patented July 19, 1932l UNITED STATESrATENT ori-lcs MILTON TLBBETTS, OF DETROIT, MIC-HIGAN, ASSIGNOR TO PAC MOTOR CAIR, COM- PANY, F DETROIT, MICHIGAN, A

CORPORATION 0F MICHIGAN Moron VEHICLE Application led October 31, 1931. -Serial No. 572,426.

This invention relates to motor vehicles and .more particularly to the elimination of the of approximately the same magni-tude.

vibration absorbing 4tedtoa It is another object of the invention to dampen vibration in a motor vehicle constituting a primary vibratory system by as-A sociating therewith a secondary vibratory system the vibrations of which oppose and neutralize the vibrations set up in the primary system due to road shocks.

"A further object comprises the provision with those parts in an automobile which are subject to shimmy vibration, supported masses which operate in sympathy and in opposite phase to the shimmy vibrations and which are designed to be of such proportions as to electively absorb such vibrations at their inception.

Still another object of the invention resides in resiliently mounting a secondary mass in rubber on the parts of a motor vehicle forming a primary vibratory system.

Other objects and advantages will become apparent to those skilled in the art from a reading of the description taken in connection with the accompanying drawing and in which:

Fig. l is a top plan view of a vehicle bumper construction embodying the features of the invention.

Fig. is a sectional view taken substantially on the line 2-2 of Fig. and looking in the direction indicated.

Fig. 3 is an enlarged plan view of an end of the bumper, showing the invention in connection therewith.

When road shock or Vehicle there is set up a primary vibration system constituting the chassis, frame, body and other associated elements. The initial forces tending to cause shimmy are usually rather small but conditions they build up to an extent where a noticeable shimmy and even a violent torof resiliently vibration is transmitunder certain sional vibration of the entire'vehicle occurs. ln accordance with the present invention, the eii'ect of shimmy ish without adding materially to the weight of the automobile or to its cost of manufacture.

According to the present invention, there substantially eliminated.

is provided a secondary vibration system which opposes the effect of vibrations induced into the primary vibratory system. In the secondary vibratory system, vibrations are created by energy transmitted from the primary system and which vibrations act in sympathy and in opposite phase with respect to the vibratory movements of the primary system. The secondary system is designed so that the vibrations occuring therein have a frequency and amplitude approximating those of the vibrations in the primary system thus effective]v absorbing the energy transmitted from tlie primary system and dampcning the primary oscillations. I rl`hc frequency of the secondar vibrations may be equal to or less than t e frequency of the primary Vibrations and the amplitude ofthe secondary vibrations may be equal to or preferably somewhat greater than the vibrations of the primary system. Resilient, yieldable means are also provided for resisting the vibrations of the secondary system so that the energy tending to cause shlmm in tclie primary system is effectively dissipate Referring to the drawings, 10 indicates the parallel side'members of a vehicle frame to the ends of which-a humper back bar I11 is secured b any suitable means such as by clips 12. he bumper back bar may be of any desired shape and as shown is curved at its ends to support animpact bar 13. Thevimpact bar may be secured to the ends of the back bar ll by any suitable means such as by clips 14 secured to the back' bar and the impact bar b means of bolts 15.

.Substantia ly all torsionalA vibrations or' lshunmy set up 1n the primary vibratory sysyeu ' portion im act bar 13 as by rivets 18 and are shaped to orm housings which substantially conceal the wei ht members in either top or front view. he brackets 17 comprise a top flange 19,8. bottom flange 21 and an interconnecting which may be partially circular in form. It is to'be noted that the brackets or housings 17`are of one piece construction,

- thus providing a structure which Mis very the effective surface union .16 be freely and entirely economical to manufacture. A pin or bolt 22 having a head 23 is verticall disposed between the flanges of the brac et and isr removably securedtheretoby a nut 24. The weight members 16 are adapted to encircle pins 22 between the flanges 19 and 21 of racket members and are lprovided with an enlarged vertically extendln bore. It is desirable that the weig t members resiliently supported with respect to the impact bar so that relative movement may take place between the weights and the impact bar. In accordance with thisinvention, the weight members are supported on rubber mountin s which in turn are secured to the pins 22 in t e brackets 17. As shown, these mountings comprise a cylindrical piece of rubber 26 having an axial bore therethrou h for the reception of the pins 22 and are adapted to be interposed between the peripheral surfaces of the shank portions of the pins 22 and the inner peripheral surfaces of the cylindrical weight portions 16. It is desirable that there be an between the surfaces of the rubber members and those of the pins and the weights. In the preferred form of the invention, the desired surface union is Vthe peferably secured by vulcanizing thefrubr members to the surfaces of the pins and to those of the weight members, but a surface u on between these arts of sufficient stren h may be secured y forcin a rubber cylin er into the axial bore of e weight rtions, the rubber e linder having a greater 'ameter than that o the bore. B so doing the rubber will be compressed ra ally and extended axially` to take substantiallythe form shown an to frictionally engage the surfaces of the pins will be seen that the pins 22 are fixed relative 'to the brackets 17 but that the weights 16 are mounted for limited resilient movement with respect to the brackets. It will be further understood thatthe surfaces of the weights 16 will move vertically and axially relatively to the pin portions 19 and 21 and the'weights 16. 'Itf 22 and that by so doing, the rubber, which is interposed between these opposing surfaces and has a surface union therlewith, will be placed in shear to yieldmg y the fact that the rubber acts in shear, the weights 16 will be very sensitive to vibratory impulses imparted to them through the vibratory system. ,l Y

The thickness and elastic properties of the rubber members 26 and the.A weight of the weight portions 16 are so proportioned that the natural period of vibration of the weights 16 is approximately equal to the period of resist such movement. By reason of shimmy. vibration of the yprimary system,

with'the result that as soon as the primary system begins to sbimmy, the weights 16 will begin to vibrate in sympathy therewith and in substantially opposite phase thereto and `in a vertical direction, dueto the relations of the natural` vibrations of the two systems. The energy causing the vibrations of the weights 16 will be taken up or absorbed through the rubber mountings.

From the foregoing, it will be apparent that an ecient and inexpensive device has been provided whereby the vibrations set up in the parts of a vehicle forming a primary vibrator system are effectively dampened and dissipated so that little 'or no shimrny is apparent to an occupant of the vehicle. The device illustrated is very economical to manufacture both as regards the parts thereof and their assembly.

It will be appreciated that the constructions described and illustrated as the prefer-'red form may be varied to a considerab e extent without departing from the concept of the invention. For example, a sleeve member may be interposed between the surfacesdf the pins 22 and those of the rubber inserts 26 having its ends in abuttin rela-v tions with the inner surfaces of the anged of the brackets and having its outer peripheral surfaces bonded to the surfaces of the rubber. By such construction, the weight and rubber assembly may be accomplished separately from that of the bracket and would be easily removable therefrom. lt will also members 17 may be formed to provide merely brackets, and need not be extended to form covers for the weights and the rubber portions, as shown.

llt will be apparent to art that the invention as illustrated is susceptible of various other changes in construction and design without departing from the spirit'or onl by aving thus is claimed and ters Patent is:

1. 1n a vehicle bum r structure, the combination of an impact ar, and a weight carried solely bythe impact bar.

2. Ina vehicle bumper structure having the appended claims.

Let-

desired to be secured by those skilled in the described the invention, whatl be seen that the bracket A ber.

an impact bar, a'resilient mounting carried solely by theimpact bar, and a mass support.

ed by the resilient mounting.

3. In a vehicle bumper structure havingan impact bar, a resilient mounting carried solely by the impact bar, and a mass entirely supported by the resilient mounting.

4. In a vehicle bumper structure having an 7. In a vehicle having parts forming a primary vibratory system, a secondary vibratory system comprisin a pin mounted on one of the parts of the primary system, a vibration absorbing mass positioned'adjacent the pin for movement relative thereto, and a resilient mounting interposed between the pin and the mass, said resilient mounting having a surface union with the pin and the mass to yieldingly secure them together, whereby the mass will be permitted to move relatively to the pin.

8. In a vehicle having parts forming a rimary vibratory system, a secondary vi ratory system comprising a pin mounted on one of vthe parts of the primary system, a vibration absorbing weight positioned vadjacent the pin for movement relative thereto, and a rubber mounting interposed between the pin and the weight, said rubber mounting having a surfaceunion with the pin and the weight to yieldingly secure them together,

whereby the weight will be permitted to move relativelyto the in.

9. In a vehicle aving a part of a primary vibrato system, a brac bumper forming a et 11. In a bumper structure for vehicles, a one-piece bracket secured to a portion of the bum er, a rubber mounting carried by the brac et, andawei ht supported by the bracket, said bracket orming a one-piece cover o adapted to partially` conceal the rubber mounting and the weight. v

12. A vehicle structure comprisin an impact bar, a rubber mounting secure to each end of the impact bar and carried solely l thereby and a'weight supported on each of the rubber mountings, sald weights being vibratable in a verticalvplane relative to the im ac t bar. y

n testimony whereof I aflix my si nature.

MILTON TIBB TTS.

on the bumper, a pin carried bythe bracket, I

a rubber mounting secured to the pin and having a surface union therewith, and a v1 bratable mass secured to the rubber mounting, saidrubbe'r mounting resisting the vibratory movements of t shearing action of the rubber.

10. In a bumper structure for vehicles,.a

one-piece bracket secured to a. portion of the bumper,- a rubber mounting sup rted bythe e mass through bracket, and a weight su porte by the rublli 

